移动端左右滑动代码

　　　　//左右滑动切换
var nStartY;
var nStartX;
var nChangY;
var nChangX;
document.getElementsByTagName('body')[0].addEventListener('touchstart',function(e){
nStartY = e.targetTouches[0].pageY;
nStartX = e.targetTouches[0].pageX;
});
document.getElementsByTagName('body')[0].addEventListener('touchmove',function(e){
e.preventDefault();
});
document.getElementsByTagName('body')[0].addEventListener('touchend',function(e){
nChangY = e.changedTouches[0].pageY;
nChangX = e.changedTouches[0].pageX;
var distance = nChangX - nStartX;
var distance1 = nChangY - nStartY;

if(distance > 50){//左滑
alert('左滑');
}else if(distance < -50){

alert('右滑');
}
});